5. PLECOGLOSSUS. 1 G5 



may prove to be more closely allied on comparison of actual speci- 

 mens. The following notes are an abstract of Giildenstiidt's de- 

 scription : — 



Salmo leucichthys, Giildemt. Nov. Comin. Petroj-). xvi. p. 533 ; Pall. 



Zoogr. Ross.- As. iii. p. 392. 

 nelma, Pull. It. ii. p. 71G ; Lepeclun, Eeise, ii. p. 192, taf. 9. 



figs. 1-3. 



B. 10. D. 15. A. 14. V. 11. [Vert. 65, LepecMn']. 



Statura et magnitiido S. .mlaris. Rostrum obtusissimum ; man- 

 dibula superior latissima, Integra, recta ; inferior adsceiidens, sub- 

 conica, apice tuberculoso, ante superiorcm prominens ; utraque 

 edentula ; rictus terminalis amplissimus, quadratus ; lingua trian- 

 gularis, soluta, subaspera ; oris cavitas alba, immaculata ; palatum 

 latum, planum, antrorsum utrinque subasperum denticulis minimis, 

 taotu, non visu, percipiendis ; nares medium inter rostrum ct oculum 

 occupantes, apertiira utrinque gemina, angusta; oculi latcrales, 

 liberi, ampli. Squamae pro mole piscis baud adco magnae. Anus 

 caudae multo propior, quam capiti, proximo ante pinnam ani, apcr- 

 tui'a duplici. 



Magnitude tripedalis vulgo, non raro ultra. 



Caspian Sea ; periodically asccuding the Wolga and other rivers 

 of Russia. According to Lepechin and Pallas the same species 

 would be found in the Arctic Ocean, ascending the rivers Ob, Lena, 

 Kolima, ifec. 



5. PLECOGLOSSUS. 



Plecoglossus, Sclilefj. Faun. Japon. Poiss. p. 229. 



Body covered with very small scales. Cleft of the mouth wide ; 

 maxUlary long. Dentition feeble: iutermaxillaries with a few 

 small, conical, poihted teeth ; the teeth of the maxillaries and man- 

 dibles are lameUiform, broad, truncated, lameUated and serrated, 

 moveable, seated in a fold of the skin ; the mandibles terminate 

 each in a small knob, and are not joined at the symphysis. The 

 mucosa in the interior of the mouth between the termiiial halves 

 of the mandibles forms a peculiar organ, being raised into folds, 

 with a pair of pouches in front and a single one behind. Tongue 

 very small, with minute teeth, its apical part being toothless ; palate 

 apparently without teeth*. Pyloric appendages in great number ; 

 ova small. 



Japan and Formosa. 



1. Plecoglossus altivelis. 



Salmo (Plecoglossus) altivelis, Schleg. I. c. pi. 105. fig. 1. 

 B. 7. D. 12. A. 16. V. 8. L. lat. 140. Vert. 64. 

 The height of the body is equal to, or rather less than, the length 

 of the head, which is two-ninths of the total (without caudal) ; 

 head rather compressed ; snout moderately produced, with its ex- 

 tremity soft and slightly swollen. Eye of moderate size. The 

 * Schlegel mentions a band of villiform teeth on each side of the jialate. 



